The random copolymers of styrene (St) and 4-vinylpyridine (4-VP) with hydroxyl end group and low polydispersities were synthesized by nitroxide-mediated living radical polymerization initiated by azobisisobutyronitrile (AIBN) and 4-hydroxyl-2,2,6,6-tetramethylpiperidineoxyl (TEMPO-OH). The experimental results have shown that all synthesized copolymers have narrow molecular weight distribution. The conversion of monomers and the molecular weight of copolymer increased with polymerization time. The copolymerization rate is affected by molar ratios of HTEMPO to AIBN. H-1-Nuclear magnetic resonance spectra shows that one end of copolymers was capped by TEMPO-OH moiety. The use of this method permits the copolymer with hydroxyl chain end and controllable molecular weight and molecular weight distribution. (C) 2003 Wiley Periodicals, Inc.